Till Büttner

Impact of Silane and Siloxane Based Hydrophobic Powder on Cement-Based Mortar

Impact of the addition of silane and siloxane based hydrophobic powders on cement based mortar was studied. Effect of powder addition on mechanical properties and water absorption of cement based mortar is described. Impact of accelerated ageing, including UV radiation, and rain-sun cycles on hydrophobic performance was assessed, demonstrating excellent durability of silane-based hydrophobic performance.

Durability aspects of AR-glass-reinforcement in textile reinforced concrete, Part 1: Material behaviour

Textile reinforced concrete (TRC) is an innovative material for thin-walled, structural elements with a high load-bearing capacity. For a safe design of TRC load bearing structures ambitious investigations were carried out to predict the time-dependent loss of strength of the AR-glass reinforcement embedded in fine grained concrete as a consequence of weathering. In the present paper possible reasons for the loss of strength of state-of-the art AR-glass reinforcement in nowadays cementitious mixtures are described and their relative importance is discussed, based on new results. In the accompanying paper (part 2), these results are used to present a durability model under complex weathering conditions.

Textile reinforced concrete : Durability issues: Changes of the bond and tensile strength due to ageing

Textile reinforced concrete (TRC) is one promising possibility to produce thin-walled high load bearing structural elements. Besides the maximum load bearing capacity, the durability under various conditions is one major issue for future applications. Usually AR-(Alkali-Resistant)-Glass is used as reinforcement. Even if it is AR-Glass, the high alkaline environment in concrete leads to a loss of the tensile strength.

Durability aspects of AR-glass-reinforcement in textile reinforced concrete, Part 2: Modelling and exposure to outdoor weathering

For a safe design of TRC (Textile reinforced concrete) load bearing structures the loss of strength of TRC as a consequence of weathering should be modelled. In part 1, possible reasons for the loss of strength of a state-of-the art AR-glass textile reinforced concrete were discussed. These findings are first used in this paper as a base for a corrosion model, describing the loss of strength in lab conditions. Subsequently, temperature and humidity were continuously measured during outdoor weathering and implemented into the model.